Besides what everyone else has mentioned there was a recap post in this thread about her Bannerlord stream last week where she supposedly went into more detail about her reasons for leaving, but it's mostly the same as what has already been mentioned.
Yeah I was honestly thinking the same thing, with all the mentions of her traveling to meet her branch mates, taking a break, participating in that marathon and maybe going to therapy. Also I love how one of her reasons for graduating is for mental health reasons but she has already installed League
I really hope she does that. I don't know if she'll be able to un-graduate, but maybe return as an indie Vtuber, or hell, even as part of Vshojo. I'll take anything as long as I can see her again and maybe interact on-stream with her genmates.
I don't know if I'm the only one but this long graduation stream is making me have some mixed feelings: on one side this is the last chance Nina will have to interact on stream with people from Niji and the fact that Ethyria will have one less member sucks, but on the other hand all these conversations make really clear that everyone will still mantain contact with Nina and nothing will change besides not being coworkers anymore and that we'll hear nothing from her except if someone who meets her wants to talk about it.